Implemented bed bouncing

src/block/Block.php

@@ -562,6 +562,14 @@ class Block{
 		return true;
 	}
 
+	/**
+	 * Called when an entity lands on this block (usually due to falling).
+	 * @return float|null The new vertical velocity of the entity, or null if unchanged.
+	 */
+	public function onEntityLand(Entity $entity) : ?float{
+		return null;
+	}
+
 	/**
 	 * @return AxisAlignedBB[]
 	 */